Capt. Todd Christiansen, from the Rock County Sheriff's Office, said investigators are widening their search to Illinois. Police are looking for a dark-colored 2004 to 2007 Infinity QX56, and the driver who left the scene after colliding with the two motorcyclists.

"Two people are dead here. Their families deserve to know an answer. It's hard to comprehend how someone can do that and walk away from it," Christiansen said.

Deborah Lipke has known 24-year-old Mitchell Vance since he was 3 and he had become like another son to her. Lipke visited the site of the crash Tuesday, still searching for answers.

"It’s disbelief; you just don't know how to feel. You keep waiting to wake up from this nightmare but it's not a nightmare. We are not going to wake up from it," Lipke said.

Eighteen-year old Devin Julius, who recently moved to Janesville, had no immediate family in the area. Lipke said it was important to her to place another cross at the memorial site in his honor.

"I've brought angels and said prayers for him. He is a part of our family and his is too far away to do this, so we are doing it for them," Lipke said.

Three other motorcyclists and another vehicle avoided the crash. Detectives found two pieces of debris at the scene, and a local dealership traced it back to the Infiniti SUV.

So far, detectives have no leads on locating the vehicle and are asking for the public's help. As for friends and family, Lipke said she hopes the driver will come forward.

"They need to come forward, and they need to admit what they did. They can't keep denying it. It's a terrible tragedy and I'm sure it's hard for them. They will have to live with this for the rest of their lives. Justice needs to be done, it's not going to bring the boys back, but it needs to be done," Lipke said.

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